Even for ERW steel pipe, we should classify the OD and WT. Different specifications of them would lead to different concerns for the engineering project. Under this situation, it is necessary to figure out the relative parameters before wholesale.

Here is the list for the API 5L/ASTM A53 GR.B of the small diameter ERW steel pipe. We can figure out that each classification of outside diameter would have three classification of wall thickness with it. Thus we should do the research before buying or we can just ask for advice from steel pipe manufacturers to figure this out.